1. Field of the Invention
The present invention relates to a method of evaluating drug sensitivity by analyzing GIRK channel genes.
2. Description of the Related Art
Pain is a pathology which is most frequently observed in the medical field, and it is often the case that the pain accompanying a disease is serious for the patient rather than the disease itself. The pain sensation plays an important role in terms of a biological warning system, however, excessive pain significantly decreases QOL (quality of life) unless it is properly controlled. Recently, importance of pain control has been recognized, palliative care including pain therapy has remarkably progressed, and there is a tendency of increasing the frequency and amount of use of various analgesics.
Heretofore, pharmacological analyses using a Xenopus oocyte protein expression system and weaver mutant mice, it has been known that a G protein-activated inwardly rectifying potassium channel (hereinafter referred to as a GIRK channel) plays an extremely important role in the molecular mechanism of analgesia by morphine, an alcohol or the like (Ikeda, K. et al., Involvement of G-protein-activated inwardly rectifying K+ (GIRK) channels in opioid-induced analgesia, Neurosci. Res., (2000) 38: 111-114.; Kobayashi, T. et al., Ethanol opens G-protein-activated inwardly rectifying K+ channels, Nature Neurosci., (1999) 2: 1091-1097.; Ikeda, K. et al., Molecular mechanisms of analgesia induced by opioids and ethanol: is the GIRK channel one of the keys?, Neurosci. Res., (2002) 44: 121-131.; and Kobayashi, T. et al., G protein-activated inwardly rectifying potassium channels as potential therapeutic targets., Current Pharmaceutical Design in press.). Further, the genetic mechanism of sensitivity to morphine is becoming clear (Ikeda, K. et al., How individual sensitivity to opiates can be predicted by gene analyses., Trends Pharmacol. Sci., (2005) 26: 311-317.).